Bueller178

So in getting my annual service done there was an ECM flash that the dealer did.

Now when the car is warm, when starting most of the time it does a high idle run for a similar amount of time it used to do only when doing a cold start.

Anybody else experience this and does this sound right?

HTXgearhead

Bueller178

Hmmm, I guess I'll be back to the dealer again......

Star4life

i dont think its an issue. i believe mine now does that as well. I just updated my vehicle as well.

Lachoufe

Personally wouldnt mind a louder start when warm... Im doing my service next monday will update if its the same for me

Dieseldan9

iTrader: (1)

What year is your car?

Did you ask them to flash it or did they do it without you asking ?


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Bueller178

It's a 2017 and it was apparently listed in their system as needing the SW update (I think it did other things as well as my bluetooth seems to connect to my phone quicker) so they did it as part of the B Service.

While I Like the bark when it starts, it takes quite a while for the idle to settle down just like if the engine was stone cold.

I'll query the dealer next time I'm around there.

RichardCranium3

I had mine in yesterday for airbag recall, rattle fixes and the trim piece where the center console button is was delaminating. They stated they did a fuel system software update that was recommended and I'm now seeing this as well. I don't see how the slightly higher start-up RPM could be an issue, so long as the RPMs eventually run back down to normal idle. Nothing to worry about in my book.

Bueller178

Putting it into gear from 1400 rpms would be a bit harsh on the trans would be my first concern.
So what I'm doing is waiting for it to settle down first but that of course means waiting around while it decides what it's doing.
I'm just curious why it needs to do it at all, it's essentially emulating a cold start but that's not necessary when everything is already toasty warm.

lboudreau

Experiencing the exact same thing here. Dealer says its normal even though it wasn't doing it prior to the update. Also lost the shift UP indicator in manual mode. Only the color indicators remain.

ShakyTom

They still haven't fixed that huh? Lost my "UP" thing probably 9 months ago now.

lboudreau

I'm hoping with persistence they'll address it. It's going back this week for some other stuff. I've also noticed boost is very inconsistent after it "cold" starts again. I don't believe this latest software update is completely bug free.

golfman

Greetings. I just got the flash as well.

After the 30 minute drive back to work, I scrolled through to check my mileage.

NO MPG calculations. Not on trip. Not on Effeciency (?) graph.

Back to dealership through 30 minutes of Christmas shopping traffic craziness.

aggies15

I had mine updated on Tuesday. Now when I start the car in Sports+, the exhaust crackles and pops 3-4 times (sounds amazing). I lost my tune so I'll have to redo that but it's solid for now. I also noticed that the car stays in high RPMs for MUCH longer in Sports+ with the update. I used to do a ton of highway driving in that mode and it was always "comfortable". Now it's impossible to drive in that mode without manually shifting or dealing with really high RPMs (not complaining, just a change I noticed).

foxberry

I'm bringing mine in for the 40k Service B in about 2 weeks. Is this ECM flash update happening across the board to everyone?

lboudreau

Looks like someone else is having the same cold start issue even when the car is warmed up.

Zoran Seat

Hi All

im having tge same issue with my GLE500 in Australia after tge SW update.

did anyone manage to solve this and return the engine to normal hot start ie no warm up
thank you

AMGzee

I brought my car in for B service and yeah noticed the same thing.. Its weird why the update would make it start like cold? I wonder why they did that, or if its a glitch in the update?

BoyGeezy

I have noticed the higher idle as well. I have a 2017, took it to the dealership a few weeks back. They flashed my ecu with an update even though I was there to get the adaptation reset/adjusted on the tcu. I really don't mind it.

W205C43PFL

I read a thread that talks about a similar problem: https://mbworld.org/forums/c450-c43-...r-updates.html
Had this exact same problem, although mine triggered after a TCU update (unless they updated something else as well and didn't note it down on the work order) since a year and a half ago. Notice all the 2019 does it so I guess that is intended behaviour. My dealership also said it was normal just like everyone else. Cold start is mostly meant to heat up the cats so I guess MB created the update to force a cold start due to regulations. However, I am not aware that other brands do this.

swift45

I just had my 2017 SL550 with 11K miles at the dealership for update. Idle is very similar during warm startups as well as cold start ups. We also own a 2014 E550 with 38K miles that only has the fast idle during cold starts! I asked the dealer to explain the difference, and was told the starting with 2017 the injection system in the 4.7 motor is very similar to a Diesel engine.
Based on that response I guess the higher idle regardless of the temperature of the engine is normal?
I also find it troubling having to wait for the RPM to settle back to normal on the warm engine prior to placing it in gear, to avoid causing any damage to the to my vehicle.
Does anyone know if putting it in gear while it’s idling fast is OK? Or if would it cause damage?

2017c43Dan

hey man I just got that software update done today on the control unit. My 2017 c43 is also high revving at warm temps now. What did you do about the issue. I think it’s normal with this update but don’t see why it’s necessary. I guess it’s a nice touch to sound louder but hope it doesn’t harm the engine.

2017c43Dan

so is the high revs on warm starts normal now?

W205C43PFL

Yes intended behaviour, all our cars that did this update has this behaviour after sitting for more than 20 minutes. All facelift C 43 (MY19+) has it out of the box, I think even all 2019 MBs across the range also does it.